Post office boxes are rented to customers for a fee by the United States Postal Service. The boxes are individually and uniquely numbered within each post office branch that provides this service for its customers. The boxes are physically located in the post office station building. Customers usually gain access to their boxes through the lobby of the post office station building. Each box requires either a combination or a key to gain access to its contents.
While a certain number of boxes are rented to corporations and other businesses, a great number of boxes are rented to individuals. In general, such individuals receive less mail than do businesses. Whereas a post office box rented by a business is likely to be accessed by an employee every work day, this procedure may not be necessary for a box rented by an individual holder.
It is not improbable that an individual may receive no mail during a given 24 hour period. In such cases, it is often frustrating for an individual to journey to the post office station at which his box is located only to find that it is empty. Moreover, such fruitless trips are wasteful of human time, energy and gas and oil required to operate most transportation vehicles. Unnecessary congestion occurs both on the roads and in the post office station.
The problem of the detecting the presence of articles in a container, and more specifically, mail pieces in a box, is an old one. Systems, such as those hereinafter discussed, have been designed to apprize tenants in apartment buildings, lodgers in hotels, and rural mailbox users that mail has been delivered.
U.S. Pat. No. 2,968,804, for example, shows a system for indicating the presence of mail in a rural box or in a container for use in an apartment building. The system described therein uses a buzzer or a light to indicate the presence of mail to the individual in his room. This reference uses a light source and photoelectric cell to determine whether the box is empty. The system is hard wired, i.e., wires connected to the box are run directly to the individual's room. This system, while adequate for use in a rural residence or apartment, is definitely not feasible for use by individuals renting boxes from their post office station. Obviously, since some post office box holders live many miles from their post office station, it would be impractical to run wires from the box directly to their residences.
Similarly, U.S. Pat. No. 2,465,935, which teaches the use of an electric circuit for actuating a lamp and buzzer after mail has been deposited in an apartment mailbox, is a hard wired system and therefore unfeasible to satisfy the objects of the present invention.
U.S. Pat. No. 2,454,088 describes a system for remotely indicating the presence of mail at a registration desk of a hotel. Once again, however, this system requires hard wiring between the box and the indicator electric light with which it is associated. Moreover, the technique for triggering actuation of the indicator lights is a manual system which relies on the hotel clerk positioning the switch at appropriate times. Such an unautomated system is, of course, subject to error.
U.S. Pat. No. 3,426,326 teaches the use of an inventory control system for determining the quantity of items of inventory in a warehouse. A plurality of sensors is located throughout the quantity of goods to be inventoried to provide measurements indicative of the quantity of particular types of goods. This system is automated in that the computer polls lines associated with locations in the warehouse, but once again wires are run directly from the warehouse location to a central computer.
The present invention overcomes the limitations inherent in the systems described in the references cited above as they pertain to detecting the presence of an article in a container. Specifically, the present invention is intended to detect the presence of mail in a post office box from a truly remote location.